Pre-oxidized PAN Nanofibrous Membrane to Efficiently and Continuously Separate Large-Scale Viscous Oil-in-Water Emulsions Under Harsh Conditions with Ultra-Long-Term Oil-Fouling Recovery

Abstract

High-performance multifunctional filtration membranes are highly required in treating practically complex oily wastewater systems, but still a challenge unsolved. Herein, we propose a facile route to address these challenges simultaneously by simply constructing electrospun pre-oxidized polyacrylonitrile nanofibrous membrane (p-PAN NM). Given the pre-oxidation process, the p-PAN NM displays not only robust anti-corrosive tolerance against diverse corrosive media, but also superhydrophilicity/underwater superoleophobicity. Additionally, ~ 99% separation efficiency, ~ 100% oil-fouling recovery, and ultra-long service life (up to 265 h) have been realized in separating large-scale surfactant stabilized soybean/crude oil-in-water emulsions. Furthermore, strong anti-corrosive performance against various corrosive media (e.g., 1 M HCl, 1 M NaOH, or 10 wt% NaCl) has been achieved as well. Spin-unrestricted density functional theory (DFT) computations implemented in the Dmol3 modulus has been conducted to understand the robust fouling recovery and the variation of surficial wettability after pre-oxidation. These outstanding filtration functions make our NM hold great potential in separating viscous oil/water emulsions under harsh conditions.

Funding

National Natural Science Foundation of China(52273055)

State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(PLN202205)

Sichuan Engineering Technology Research Center of Basalt Fiber Composites Development and Application(2022SCXWYXWFC006)

Natural Science Foundation of Sichuan Province(2022NSFSC0356)